Getting Class information

I have the absolute path to a Java Class File. For this Class I need to find information like the methods/package information/ etc. Which is the cleanest and easiest way to do this. Can some one explain this or point to any examples?

Since this is duplicated in Intermediate here, I'm closing this thread. (Otherwise people waste time rplying to things that have already been answered.) Folks can still add to the answer in Intermediate if they wish, of course...